The present invention relates to an electric machine with improved heat management, wherein the electric machine is a so called wet rotor machine with a split cage, which separates a wet region from a dry region.
Electric machines in the form of EC wet rotor motors are known in various configurations and are generally used for applications in which a rotary movement is produced in the medium and a dynamic sealing is avoided. One use sector is pumps, for example. In order to achieve physical forms which are as small as possible, control electronics, for example in the form of a printed circuit board, are integrated in a dry region of the electric machine. In this case, the rotor is arranged in the wet region and the stator is arranged in the dry region, wherein generally only internal rotor motors are implemented since the splash losses in the wet region are otherwise overproportionally great in the case of large rotor diameters. Owing to the integration of the control electronics in the dry region of the electric machine in combination with high ambient temperatures, high thermal loads result. Owing to the integration in a very narrow physical space, high temperatures result both at the winding of the electric machine and in the component parts of the electronics. The heat produced in the stator or the stator winding is in this case conducted via a good thermal connection, for example via short copper lines with good thermal conductivity and often having large cross sections and/or is conducted directly onto the control electronics from the stator via thermal radiation.